Portal is free (again) until September 20th

In their continuing effort to prove that their the best damn game company in the business, Valve has decided to give out (once again) the original Portal for free.  If you haven’t played it yet, what the hell is wrong with you?

Excuse me.  What I meant is you should pick up one of the most meme-filled games ever, and start working towards your cake.  You can pick up the game on Steam, but you must do so before September 20th, which is when everyone will disappear to the 360 for a little something called Gears of War 3.

Steam!